Incoming flights were halted at Detroit Metropolitan Wayne County Airport on Thursday morning due to thunderstorms after heavy rain overnight caused flooding that had already partially blocked access to the airport.
Detroit Metropolitan Wayne County Airport is under a ground stop until at least 11 a.m. ET, according to the Federal Aviation Administration.
Three inches of rain fell on the airport over about five hours, according to the National Weather Service, causing some flooding.
"Currently, travelers cannot access the McNamara Terminal due to flooding in the Dingell Drive tunnels. Customers with flights operating out of the McNamara Terminal are encouraged to contact their airlines with any questions about their flight status," the airport said.
According to FlightAware, 15% of flights originating in Detroit have been delayed and 9% have been canceled, while 9% of flights heading to Detroit have been delayed and 8% have been canceled.
Detroit Metropolitan Airport (DTW) is a major hub for both Delta and Spirit and has more than 1,100 flights per day, according to its website.
The rain is connected to a broader risk of severe storms and flooding in the Great Lakes area.
A level 2 of 4 risk for flooding extends from Ohio into Pennsylvania, and the threat for severe storms includes over 40 million people over the Great Lakes, including Chicago, Detroit and Cleveland, where more strong to severe storms are expected.
This is a developing story that will be updated.